chore(nvim): add oil.nvim

This makes easier to handle with folders and files.

config/nvim/lua/custom/plugins/init.lua

@@ -109,5 +109,13 @@ return {
         { '<leader>mc', '<cmd>ToggleTermSendCurrentLine<cr>', desc = 'Send [c]urrent line under the cursor', noremap = true }
       }
     end
-  }
+  },
+  {
+    'stevearc/oil.nvim',
+    dependencies = { "nvim-tree/nvim-web-devicons" },
+    keys = {
+      { '-', '<cmd>Oil<cr>', desc = "Open parent directory" },
+    },
+    opts = {},
+  },
 }